In her history class, Vanessa took 5 quizzes. Her scores were 85, 77, 94, 88, and 91. What was her average score on the quizzes?
Answer: The average is the sum of her scores divided by the number of scores. There are 5 scores and their sum is $85 + 77 + 94 + 88 + 91 = 435$ Her average score is $435 \div 5 = 87$.